JPS62266594A - Plasma display unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a plasma display device.

[Conventional technology]

A conventional plasma display device will be explained with reference to FIG. The plasma display panel 1 has m row electrodes 2I to 2m that are parallel to each other, and n column electrodes 3I to 3m that are parallel to each other and arranged in a matrix opposite to these. A display cell 4 is formed. The scanning signal unit 9 receives the clock pulse a from the clock generator 8 and generates a scanning signal with a constant period synchronized with the clock pulse a.
Row electrode 2. .about.2m are connected to the row driver 5 through output lines corresponding to the row drivers 5 and 2m, and scanning signals are inputted from the scanning signal section 9 to sequentially scan the row driver 5.

The row driver 5 has an output terminal connected to each of the row electrodes 21 to 2m in a corresponding manner, and during a period when the discharge pulse C is inputted from the discharge pulse generation section 7 and is scanned by the one row control section 11, the corresponding output terminal is connected to each of the row electrodes 21 to 2m. A discharge pulse C is stepped up and applied to one side of the row electrodes 21 to 2m to a voltage necessary for discharge. The data control unit 12 is connected to the column driver 6 through output lines corresponding to each of the column electrodes 31 to 3n, and the input data d output from the input data unit 10 is applied to the scanning of the row electrodes 2 to 2m. Correspondingly, each time a clock pulse a is input, the 0 column driver 6 is inputted to the data control unit 11, arranged as a signal to the corresponding row electrode, and outputted to the output line to the corresponding column driver 6. , the output of the data control unit 12 and the discharge pulse C are input, and the discharge pulse C is stepped up to the voltage necessary for discharge and applied to the selected column electrode. In this case, since the discharge voltages applied to the corresponding row electrodes and column electrodes are controlled to have opposite phases to each other, the discharge voltages are additively applied to the display cell 4 at the intersection of both electrodes, and the display The cell 4 becomes higher than the discharge opening voltage and emits light by discharging.

As described above, the scanning of the row electrodes 21 to 2m and the scanning of the column electrodes 31 to 3m
By synchronizing the input timing of input data d to n and selectively controlling the column electrodes corresponding to the row electrodes scanned according to the input data d, a display cell corresponding to the input data d on the plasma display panel 1 is generated. 4 can be made to emit light. The luminance at this time depends on the frequency of the discharge pulse C output by the discharge pulse generator 7.

[Problem that the invention seeks to solve]

The above-mentioned conventional plasma display device.

Since the discharge pulse generator always generates discharge pulses regardless of the scanning signal, the number of discharge pulses applied within the scanning period of each row electrode is 1 or 2 depending on the phase relationship between the scanning signal and the discharge pulse. In such a case, the luminance of one display cell is proportional to the number of discharge pulses, so there is a drawback that the luminance appears to the human eye as stripes with uneven luminance in the scanning direction. For better control, the frequency of the discharge pulse applied to both electrodes in one row is changed, which has the disadvantage that the above-mentioned uneven brightness stripes also occur.

[Means for solving problems]

The plasma display device of the present invention counts the number of discharge pulses output for each scanning period of one row of electrodes, and when the count value reaches a set value, stops outputting subsequent discharge pulses and starts counting. It has a pulse control section for clearing the value, and a setting means for setting the set value of the discharge pulse in the pulse control section.

In this way, the number of discharge pulses applied to the row electrodes and the corresponding column electrodes during one scanning period can be set in advance and kept constant, so that the light emission of the display panel does not cause stripes due to uneven brightness. do not have. Further, even if the luminance of the light emitted from the outside is changed, it is possible to similarly prevent the occurrence of stripes due to uneven luminance.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a plasma display device of the present invention.

On the wood flow side, a pulse number setting section 13 and a pulse control section 14 are installed in the conventional apparatus described with reference to FIG. The pulse number setting unit 13 outputs a pre-up-2 signal e using polyurethane or the like, and presets the number of discharge pulses C that the pulse control unit 14 should output during one scanning period. The pulse control unit 14 inputs the scanning signal S and the discharge pulse C, counts the input discharge pulse C from the start of scanning by the scanning signal S, and outputs the discharge pulse C to the row driver 5 and the column driver 6. discharge pulse C
When the number becomes equal to the value set by the preset signal e, the output of subsequent discharge pulses C is stopped, the count value is cleared, and the same operation is repeated every scanning period.

In this way, the number of discharge pulses during one scanning period of the display cell 4 is always maintained at the preset value e, so that stripes do not occur and the brightness can be controlled without causing brightness unevenness.

〔Effect of the invention〕

As explained above, the present invention uses a pulse control section and a setting means for setting a discharge pulse count value in the pulse control section to preset the number of discharge pulses to be output during one scanning period of each row electrode. By keeping the value constant in accordance with the set value, there is an effect that the brightness can be controlled without producing stripes due to uneven brightness, and without producing stripes due to uneven brightness.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the plasma display device of the present invention, and FIG. 2 is a block diagram showing a conventional plasma display device. 1...Plasma display panel, 2□~2m...row electrodes, 31~3n...column electrodes, 4...... ...Display cell, 5...
・・・・・・・・・・・・Row driver, 6・・・・・・
・・・・・・・・・Column driver, 7・・・・・・・・・
・・・・・・Discharge pulse generation part, 8・・・・・・・・・
・・・・・・Clock generator, 9・・・・・・・・・・・・
・・・・・・Scanning signal section, lO・・・・・・・・・・・・
・・・Input data section, 11・・・・・・・・・・・・
...Line control section. 12・・・・・・・・・・・・Data control unit, 1
3・・・・・・・・・・・・Pulse number setting section, 1
4・・・・・・・・・・・・Pulse control section, a.
...Clock pulse b...Scanning signal, C...Discharge pulse, d...Input data. e...Preset signal. Patent applicant: Nippon Electric Co., Ltd. m-, agent: Patent attorney Uchihara 1P”, Japan (,1
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Claims (1)

[Claims] The display cell has a display cell formed at the intersection of a plurality of row electrodes and a plurality of column electrodes arranged in a matrix facing each other, and a row control section is synchronized with a clock pulse. During the period of scanning with the scan signal generated by the scan signal, a discharge pulse is applied to the corresponding row electrode, and each time the data control unit inputs a clock pulse, input data is read, and the column electrode corresponding to the input data is selected. In a plasma display device in which the display cell discharges and emits light by applying discharge pulses to display characters and figures corresponding to input data, the number of discharge pulses output per scanning period of the row electrodes. a pulse control unit that counts the number of discharge pulses and clears the count value by stopping the output of subsequent discharge pulses when the count value reaches a set value; and a setting means that sets the set value of the discharge pulse in the pulse control unit. A plasma display device comprising: